Process of preparing monobenzoyldiamino-anthraquinone



Patented July 12, 1932 UNITED STATES PATENT OFFICE l HANS BUCHLOH, 0F LEVERKUSEN-QN T'HE-RHINE, WALTER MIEG, OF OPLADEN, NEAR COLOGNE-ON-THE-RHINE, AND -WAI:THEB STOETZER, 01 LEVERKUSEN-ON-THE- RHINE, GERMANY, .ASSIGNORS TO GENERAL ANILIN E WORKS, INC 013 NEW YORK,

N. Y., A CORPORATION on DELAWARE PROCESS PREPARING MONOBENZOYLDIAMINQ-ANTHRAQUINONE No Drawing. Application filed November 21, 1928, Serial No. 321,034, and in Germany August 30, 1926.

The present invention relates to a process of preparing monobenzoyl,diamino-anthraquinones, more particularly it relates to a process of preparing compounds of the probable formula wherein one w stands for hydrogen and the other :1; stands for the group N ELGOU H v In accordance with the invention 1-ben- 'zoylamino-a-aminoanthraquinone and l-benzoylamino-5-aminoanthraquinone are obtainable in a convenient manner and in good yield, by heating the corresponding 'diamino-anthraquinones in the presence of an acid binding agent and of a suitable high boiling inert organic solvent, such as nitrobenzene, or tho-dichlorobenzene, trichlorobenzene and the like, with benzoylchloride in a quantity corresponding to about 120140%-0f thetheoretical amount. As acid binding media suitable for performing our process, alkali metal carbonates, magnesium oxide, calcium oxide, pyridine and its homologues, quinoline and the like may be mentioned by way of example; whereby in thecase of 1.5-diamino anthraquinone an alkali metal carbonate, especially sodium carbonate, in the case of lAl-diamino-anthraquinone sodium carbonate, py-

ridine or a homologuethereofwill yield the best results. I V

The temperatures to be used may vary in wide 'limits, mainly depending on the kind of diamino-anthraquinone and on the acid j binding agent used. For'instance, when working with 1.5-diaminoanthraquinone in the presence of sodium carbonate, tempera.- tures of about law-180 C. will be suitable ones, whereas when replacing the 1.5fdiaminoanthraquinone 1.4 -diaminoanthrauinone, temperatures between about" 10%50'? G. will yield better results,

The reaction is antageously performed by dissolving or distributing the diaminoanthraquinone in the 'orga'nici'solvent, adding the acid binding medium in'an amountat least sufficient to bind all of lthe hydrochloric acid' being liberated during the reaction, and then causing the benzoyl chloride to run in slowly while stirring and while heating the mixture to the temperatures aboye mentioned. 7 The manner of Working upthe reaction product differs according to the diaininoanthraquinone used as starting material. When starting for instance, with ll-diamino'anthraqulnone, the reaction proceeds so smoothly,that without further treatment atechni-V eally useful product results. In the case of '1-5-diaminoanthraquinone a fractional separation of the reaction product is necessary. In this case an addition of an aliphatic alcohol, especially ethylalcohol, has been found essential for carrying out the separation proci ess. By this addition the small amounts of 1.5-dibenzoyldiaminoanthraquinone having been formed simultaneously with t emono benzoyl compound, can be caused to separate,

and from the filtrate the l-benzoylan'iino 5-i aminoanthraquinone can easily be isolated in a state of purity, sufficient for usingthe. I

compound as intermediate product inflthe manufacture of dyestuffs 'without any furthercleaning; i

The following examples illustrate our in- Vention, without limiting it thereto, the parts being by weight E mample 1.To amixture of parts of 1. l-diamino-anthraquinone 500 parts of nitrobenzene, parts of collidine are added and the mixture is heated'toabout' %1'50 (1, until allwater has escaped. Afterquick- I ly cooling to 15:2Q 80 parts of benzoylchloride, dissolved in 100 partsof nitroben zene are gradually added, care being taken that the temperature not surmounts 25 C. After the addition of the benzoylchloride the temperature is maintained at about 30 70.,

until no more unchanged starting material is V to be detected microscopically.v The reaction product separates during the reaction and can be isolated by filtering. When working inthis manner the l-benzoylannno- 4-aminoanthraquinone of the formula:

NH.OO.CuHa.

ii i ILTH:

is obtainable in a good yield and in a good state of purity. It is soluble inpyridine and sulfuric acidlof 96% strength with a reddishviol'et coloration and crystallizesfrom nitrobenzene in blue-black crystals.

,Ema/mp lre 2.j To a mixture of 20 parts of l.5-diamino-anthraquinone, 336 parts'of n1- trobenzene and :10 parts of'caleined sodium carbonate, amixture'of; 13.6 parts of benzoylchloride and 27,1 parts of nitrobenzene s added within two hours 'Whilefs'tirring and while maintaining the temperature at about 150" C. The melt isstirred up with 224 parts o f ethylalcohol and filtered at about 80 (1.. The remaining1.5-dibenzoyl d1a1nino anthraquinone (obtained in small quantities). is Washed twice with 32 parts (each time) ofa mixture of equal parts of nitro benzene and alcohol.

Y the 1 benzoyla-mino-5-aminoanthraquinone is allowed'to cool over night, whereby the 1- benzoylamino5-aminoanthraquinone of the formulai I v p lynooosns separates in a very pure form and with a good yield. It is filtered at'20 C. and finally J v washed with ethylalcohol. It is soluble in sulfuric acid of 96% strength with afaintly yellow-red coloration and crystallizes from nitrobenzene in g'olden-orangeprisms.

Instead of ethylalcohol other aliphaticalcohols such as methyl,propyl-, isopropyl-,

butyl-, isobutyl alcohol and the like can be used.

' comprises heating a compound of The liquid containing 7 amino 5' aminoanthraquinone, "the the general formula Z I wherein one x stands for hydrogen and the other a: for the amino group, with benzoylchloride in the presence of a high boiling inert organic solvent and of an acid binding medium, the benzoylchloride being slowly added in a quantity corresponding to aboutv 12O 140% of the theoretical amount.

2. In the process of preparing monobenzoyl-diamino anthraquinones, the step which comprises heating a compound of the general formula 1 NHa wherein one w stands for hydrogen and the other w for the amino group, with benzoylchloride in the presence of an organic solvent of the group consisting oi nitrobenzene and ortho-dichlorobenz ene, and of an acid binding mediumin a 'quantity at least sufficient to bind all of the hydrochloric acid beingliberated during the reaction, the ben zoylchloride being slowly added in a quantity corresponding vto about -1407; of the theoretical amount.

7 3. In thefprocess of preparing l-benzoyl step which comprises heating 1.5-diaminoanthraquinone with benzoylchloride to about C. in the presence of an organic solvent of the group consisting of nitrobenzene and ortho-dichlorobenzene, and in the presence of an acid binding medium of the group consisting of the alkalilmetal carbonates, magnesium oxide and calcium oxide, the benzoylchloride being addedslowly and in a quanti- Y ty corresponding to about '120140% ofthe theoretical amount.

4. The process of preparing l-benzoyl- -amino-5-aminoanthraquinone which consists in slowly adding benzoyl chloridein a quan-- V tity corresponding to '120140% ofthe theoretical amount, while stirring, to a mixture of 1.5-diamino-anthraquinone, nitrobenzene and sodium carbonate, while maintaining the c temperature between about 140 180 C4, adding an aliphatic alcohol, filtering and cooling the filtrate until the, l-benzoylami-"l no-5-aminoanthraquinone has separated.

5. v The processwhich consists in adding to "a mixture of 20 parts by weight of 1.5-diaminoanthraquinone, 336 parts by weight of nitrobenzene and 10 parts by weight of acalcined sodium carbonate within2 hours and at a temperature of about 150 0., a mixture of 27,1 parts by weight of nitrobenzene'and' 13,6 parts by weight of benzoylchloride, adding 224c parts by weight of ethylalcohol, filtering at a temperature of about 80 C. and cooling the filtrate until the l-benzoylamino-5-amin0anthraquinone has separated.

In testimony whereof we have hereunto set our hands.

HANS BUCHLOH. L 8.] WALTER MIEG. a 8.] WALTHER STOETZER. 1,. 8.] 

